The component LONGPOLLING is an invisible component that listens to server side events.

Internally the component opens up an own http-connection to the server, which waits for an event to occur. If the event occurs then the http response is passed back to the component so that the component itself will trigger the associated ACTIONLISTENER.

On server side there is a corresponding structure that simplifies the creation of http-endpoints significantly: you need to implement a class extending "DefaultLongPolling" and  register an instance of this class in the "LongPollingMgr". The URL that is required by the component is a property of the instance as well.

Please note: there is a component WEBSOCKETPOLLING doing exactly the same thing, which is based on much more lightweight websocket communication. In case of websockest being usable in your scenario we recommend to use the WEBSOCKETPOLLING component.